Fifth virial coefficient of hard sphere mixtures

New calculations of the ® fth virial coe cient are presented for binary hard sphere mixtures. These improve on, and in some cases correct, previous results. A polynomial ® t is used to extend the results to all diameter ratios, with an accuracy better than 1.05%. It is con® rmed that the ® fth virial coe cient is positive for all diameter ratios and mole fractions